Young Males Exposed to Pesticide Endosulfan See Delay in Sexual Maturation

Study in Environmental Health Perspectives Also Finds Interference with Sex Hormone Synthesis

Male school children exposed to the pesticide endosulfan showed delayed sexual maturity compared with similar children who were not exposed, according to a study published today in the December issue of the peer-reviewed journal Environmental Health Perspectives (EHP). Endosulfan also appears to interfere with sex hormone synthesis, according to results of the study of males aged 10-19 years in a community of cashew plantations in northern Kerala, India. Although endosulfan is no longer made in the United States, an estimated 1.4-2.2 million pounds are used in the United States on crops including squash, pecans, and strawberries.

Researchers evaluated 117 boys in a village where endosulfan has been aerially sprayed for more than 20 years and 90 comparable boys from a nearby village with no such exposure history. For each group, the researchers performed physical examinations and recorded clinical history, sexual maturity rating, and blood levels of various hormones. The study found a higher prevalence of congenital abnormalities related to testicular descent in the study group, but it was not statistically significant due to a small sample size.

“Our study results suggest that endosulfan exposure may delay sexual maturity and interfere with hormone synthesis in male children,” the study authors write. “The practice of aerial spraying of endosulfan was discontinued in December 2000. Serum endosulfan residue levels were significantly higher in the study population than in the control group even 10 months after the last aerial spray.”

Endosulfan has been banned in several countries, including Cambodia, Colombia, Germany, Sweden, Norway, Indonesia, and others. Its use is severely restricted in at least 20 other countries.

Commenting on the study, Dr. Jim Burkhart, science editor for EHP, says, “This is the first human study to ever measure the effects of endosulfan on the male reproductive system. Decades of spraying this pesticide, and only this pesticide, on the village provided a unique opportunity to analyze its impact. Although the sample size is somewhat limited, the results are quite compelling.”

The lead author on the study was Habibullah Saiyed of the National Institute of Occupational Health (Indian Council of Medical Research). Other authors were Aruna Dewan, Vijay Bhatnagar, Udyavar Shenoy, Rathika Shenoy, Hirehall Rajmohan, Kumud Patel, Rekha Kashyap, Pradip Kulkarni, Bagalur Rajan, and Bhadabhai Lakkad.

EHP is the journal of the National Institute of Environmental Health Sciences, part of the U.S. Department of Health and Human Services. More information is available online at http://www.ehponline.org/.